Buckle for safety belts



Oct. 18, 1966 SMITH BUCKLE FOR SAFETY BELTS 2 Sheets-Sheet 1 Filed Sept. 29, 1964 INVENTOR.

LAWRENCE H. SMITH.

ATTORNEY Oct. 18, 1966 L. H. SMITH BUCKLE FOR SAFETY BELTS Filed Sept. 29, 1964 2 Sheets-Sheet Z FIG.4

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o .IIIIIIII'M FIG? ATTORNEY United States Patent 3,279,020 BUCKLE FOR SAFETY BELTS Lawrence H. Smith, Bloomfield Hills, Mich., assignor to Allied Chemical Corporation, New York, N.Y., a corporation of New York Filed Sept. 29, 1964, Ser. No. 400,103 Claims. (Cl. 24230) This invention relates to a buckle adapted to easily and securely join the free ends of a safety seat belt of the type employed in automobiles and more particularly to the type of buckle wherein a tongue formed of metal or plastic is attached to one of the belt ends in a relatively permanent fashion and is designed to be locked in a second buckle element fixed to the end of the other seat belt end.

Buckles of this type are known as metal-to-metal structures to distinguish them from buckles wherein a single buckle element is attached to one belt end and is adapted to receive the other belt end directly; this latter type, with which the present invention is not concerned, being termed a belt-to-metal structure.

In metal-to-rnetal buckle structures the tongue element is normally a flat metal section having an elongated slot which is adapted to receive a loop formed in a belt end so as to retain it to the belt and having an extended section with an aperture therethrough. The other buckle element has some form of channel adapted to receive the extended section of the tongue. The channel carries a lock member normally urged to a closed position with respect to the channel by means of a spring and adapted to lift out of its locked position to receive the tongue end when the tongue is manually inserted into the channel. The lock then engages the aperture in the tongue so as to firmly lock the tongue within the buckle. The lock member may be manually lifted by pulling a shell which is supported in hinged mating relationship to the buckle channel. This shell lifts the lock member out of the tongue aperture so that the tongue may be removed to open the seat belt.

It is a primary object of the present invention to provide a buckle of this type having a structure that is relatively simple and economical to fabricate, which locks so as to easily absorb all of the forces which might be exerted on the belt, is not susceptible to opening by accidental forces imposed on the buckle, and is simple to adjust with respect to its belt straps so as to accommodate occupants of varying size.

In order for the buckle to be truly safe in operation it must not only be able towithstand impact forces at least as great as those for which the belt is designed without accidentally opening but must also be easy to open manually following the termination of these forces. If a buckle were to become deformed during the application of high pressure to the belt so that it was not easy to open it would make it extremely difficult to leave a vehicle after an impact and would thus create a class of very dangerous situations.

The present invention, therefore, has an object to provide a belt buckle design which is capable of withstanding high tensile forces and which is just as easy to open following the termination of the forces as it was previously.

The same problem exists with respect to the mechanism for securing the belt to the buckle in an adjustable manner to accommodate occupants of varying size. If this mechanism were difficult to adjust it would deter the occupants from using the seat belts and thereby completely eliminate the advantages achieved by the belt. Yet this mechanism must be absolutely safe against slippage during the exertion of tensile stresses on the belt and must again be easily adjustable after the termination of these forces. It is therefore a further object of the present invention to provide a belt buckle design incorporating a belt length adjustment mechanism which completely prevents slippage of the belt during the exercise of tensile stress on the belt and which is easy to adjust at such time as no tensile forces are being exerted.

Other objects, advantages, and applications of the present invention will be made apparent by the following detailed description of a preferred embodiment of the invention. The description refers to the accompanying drawings in which:

FIGURE 1 is a perspective view of a buckle assembly formed in accordance with the present invention, fixed on the ends of a seat belt, in an open condition, with certain parts of the buckle member broken away for purposes of illustration;

FIGURE 2 is a top view of the buckle assembly in a closed position;

FIGURE 3 is a longitudinal sectional view through the buckle assembly taken along lines 3-3 of FIGURE 2;

FIGURE 4 is a top view of the buckle assembly in a closed position with the cover removed; and

FIGURE 5 is a view of the buckle assembly showing the plastic cover in section.

Referring to the drawings, the structure formed in accordance with the present invention comprises a buckle assembly generally indicated at 10 and a tongue member 12. The tongue member 12 is formed of a fiat plate which has an elongated slot 14 at one end adapted to receive a sewn loop 16 formed in the end of one belt member 18. It would be possible for the belt 18 to be joined to the tongue member 12 by means of a connection which would be adjustable so as to vary the effective length of the belt 18, but in connection with the present invention it is preferable that the joinder between the tongue 12 and its belt be a fixed one and an adjustable connection be made between the other belt member 22 and its buckle member 10. The section of the tongue member 12 which extends outwardly from the belt loop 16 has a rectangular aperture 20 formed therein which is generally rectangular and has its larger dimension in a direction transverse to the length of the belt. The aperture 20 is adapted to receive a lock member associated with the buckle 10 as will be subsequently described and its configuration might vary from that employed in the preferred embodiment. For instance it might take the form of a slot formed across the Width of the tongue 12 and having a channel communicating to the forward end of the buckle.

The buckle member 10 is formed about a channel member having a base 24 and a pair of upturned walls 26 and 28 on opposite sides. The walls 26 and 28 are preferably formed from the same sheet of steel as the base 24 and are bent upwardly at right angles with respect thereto.

The belt 22 is retained to the buckle member 10 by means of a cylindrical bar 30 having a knurled outer surface. This belt retaining bar 30 has a pair of rectangular cars 32 extending axially outward from its opposite ends. The length of the cylindrical section is slightly smaller than the distance between the outer sides of the walls 26 and 28.

The ears 32 are slidingly retained in a pair of identical slots 34 and 36 formed in the walls 26 and 28, respectively. The slots 34 and 36 are formed with a slight inclination so that their rearward ends (those ends nearest to the belt 22) are closer to the base 24 of the channel member than are their forward ends. The slots 34 are slightly wider than the cars 32 so as to allow the bar to slide along the slots but to prevent any appreciable rotation of the bar 30 about its axis. The slots are approximately inch longer than the cars 32 in the preferred embodiment of the invention so that the bar 30 may be moved approximately that distance between its forward and rear positions and is adapted to move downwardly in the direction of the base 24 as it moves toward the rear.

A slot 40 is formed in the base member 24 across the entire width of the buckle directly below the knurled bar 30. The rear end of this slot 40 is bent into an upwardly directed tab 42 which extends across the width of the base 24 adjacent the rearward ends of the slots 34 and 36.

The upper end of the tab 42 extends above the center line of slots 34 and 36 to prevent the cutting of a belt webbing supported on the bar 30 as the belt is tensioned against the tab.

The belt 22 is adapted to .be joined to the buckle member 10 by passing its extreme end up through the slot 40 around and over the bar 30 in a rearward direction and back out of the slot 40. The length of the extending belt end may be adjusted by moving the bar 30 in an upward forward direction and simply pulling the belt around the bar. When any pulling force is exerted against the belt 22 it tends to move the bar 30 in a downward rearward direction so as to lock the belt between the forward edge of the tab 42 and the bar 30. The knurl on the bar prevents the belt from sliding with respect to the bar when any tension is exerted on the belt.

This simple and secure belt connection mechanism has been tested and found to easily withstand tensile stresses in excess of 5,000 pounds exerted on the belt without allowing the belt to slip with respect to the bar or in any way deforming the buckle mechanisms so as to make it difficult to adjust the belt following the releases of the tension.

The tongue 12 is locked within the buckle 10 by means of a lock member generally indicated at 46 which is supported within the channel member on a pivot rod 48. The rod 48 is pivotably journalled in holes 50 formed in the two side walls 26 and 28. The ends of the rod 48 are peened so as to retain the rod within the holes 50. The lock member 46 has a pair of upturned side wall 52 and 54 each of which contain holes 56 through which the rod 48 passes. walls 52 and 54 is less than the distance between the inner sides of the walls 26 and 28 and the lock member is straddled by these outer walls. The lock member has a base 58 and an upturned lip 60 at its forward end. The lip 60 is positioned directly over the forward end of the channel base 24 and tongue 12 is inserted between the two.

The rear end of the lock member 46 and its upturned lip 60 receives one extending end of a wire spring 64 having a coil wound around the hinge bar 48 and its other end extending under a tab 66 bent out of the side plate 26. The spring 64 thus urges the rear end of the lock member 46 in a downward direction.

A locking tab 68 is turned downwardly from the lock member 46 adjacent to the rear edge of its base 58. The

The distance across the side tab 68 is cut out of the base 58 forming a slot 70. The

tab extends across the center part of the width of the lock member as is best seen in FIGURE 3, the tab 68 is bent downwardly from the forward side of the slot 70 so that its downwardly projecting locking lip faces the rear of the buckle member and projects below the rearward end of the slot 70. The tab 68 is relatively gently inclined with respect to the contiguous surface of the base 54 of the lock member.

As may best be seen in FIGURE 3, when the tongue 12 is manually inserted into the buckle member 10 by bringing it between the upturned lip of the lock member and the forward edge of the channel base 24 it forces the lock member to rotate about its hinge bar 48 in a a counterclockwise direction as viewed in FIGURE 3 thereby lifting the locking lip 68 off its normal resting place on the base 24. As the tongue is inserted farther the slot 20 therein passes under the locking tab 68 and allows the locking member to rotate under the force of the spring 64 to bring the tab 68 back into engagement with the base 24 thereby preventing a retracting movement of the tongue because of the engagement of the forward edge of the slot 20 with the locking tab 68. The slot 40 formed in the base member 24 of the channel has an upturned tab 69 which abuts the forward end of the tongue 12 as the tongue is inserted into the buckle member in order to limit its forward motion.

The locking member 46 also includes an upward, rearward extending opening tab 74 which is bent upward and then to the rear so that its end extends approximately parallel to the base 24.

' A release cover which may be formed of plastic acts to cover the entire mechanism of the buckle 10. It has a pair of downturned side plates 82 and 84 which have a spacing at their inner walls which is slightly larger than the spacing across the outer side walls 26 and 28 of the bracket channel. The release cover also has a sloping downwardly-turned rear wall 86 and a grip portion 88 at its forward edge. The grip portion 88 extends downwardly in front of the latch 60. This prevents the tongue from being erroneously inserted between the cover and the latch and providing a false latch. The release cover 80 is pivotably supported with respect to the bracket channel 24 by means of a pair of beaded hinge pins 90 which extend through holes 92 formed in the side walls 26 and 28 and through holes 94 formed in the side walls 82 and 84 of the release cover. 7 The heads of the pins 90 are has an open forward end and enclosed back and sides which connect with the cover member 80. The lift tab 74 enters through the open forward end of the pocket so that its lower side is disposed on the base of the pocket. A pair of side wings 101 extend from the sides of the pocket 100 in the direction of the edges of the assembly (best seen in FIGURE 1). The wings extend below tabs 103 formed from the side walls 26 and 28 and are adapted to abut the undersi-des of these tabs when the cover 80 is in its extreme released position in order to limit the motion of the cover. When the cover is in its closed position the wings 101 extend below the tabs 103.

The buckle may be actuated so as to release the tongue 12 by 1ifting the forward end 88 of the release cover 80. This causes the cover to pivot about the pins 90 so as to rotate the pocket 100 in a clockwise direction as viewed in FIGURE 3. The upper side of the pocket bears against the lift tab 74 to rotate the lock member 46 in a counterclockwise direction as viewed in FIGURE 3 and thereby lift the lock tab 68 above the level of the tongue member 12 allowing the tongue to be extracted.

The shape of the release cover 80 is such as to prevent the accidental opening of the buckle as a result of random impact forces experienced by the cover. Any forces exerted on the cover from any direction which may be reached when the belt is in a closed position will urge the cover to rotate in a counter-clockwise direction as viewed in FIGURE 3 and will therefore not have any tendency to open the lock.

Tensile forces exerted between the belt members 18 and 22 while the buckle is closed exert forces on the short downturned lock tab 68 and tend to transmit these through the plane of the lock member base 58 to the pivot rod 48 which in turn distributes them to the rigid side walls 26 and 28 of the channel. These forces do not in any way tend to distort the engagement between the release tab,

74 and the pocket 100 which cooperate to open the buckle.

The buckle is therefore capable of experiencing tensile be employed, and are therefore easily able to absorb the necessary forces.

Having thus described my invention, 1 claim:

1. In a safety belt system fora vehicle including a pair of =belt members each having one end fixed with respect to the vehicle, the first of said belt members having its other end fixed to a tongue member having an extending section and an aperture therein, a buckle operative to receive the free end of the second belt in an adjustable manner and to lockingly receive said tongue member so as to close the system, said buckle including:

a channel member having a relatively wide base and short upturned sides;

a lock member having a base and a pair of upturned sides pivotably supported with respect to the channel member on means supported by the upturned sides of the lock member;

spring means connected between said channel member and said lock member and operative to urge said lock member into a first, locked position with respect to said channel member;

a locking tab extending downwardly from said locking member and operative to abut the base of said channel member when said locking member is in its locked position;

a central upturned opening tab joined to said lock member intermediate the upturned walls thereof and having a terminal end bent substantially parallel to said lock member base; and

a release cover pivotably supported with respect to said channel member for motion about an axis parallel to the axis of pivotation of said lock member, said release cover having a grip portion, a pair of downturned side walls, a planar top and a pocket member disposed on the side of the cover top opposite the base between the axis of pivotal support of the cover and the grip portion thereof and being operative to engage said terminal end of said lock member, said release cover having a first, closed position wherein said spring means, acting through the opening tab of the lock member causes the release cover to be closed with respect to said channel member, and a second open position wherein manual forces are exerted on the release cover so as to cause it to pivot with respect to the channel member and the pocket member engages the opening tab of the lock members so as to pivot the lock member from said closed position into a second open position, whereby, when the release cover is in a closed position the tongue may be inserted between the lock member and the channel base so that the locking member extends through the aperture of the tongue and locks the tongue with respect to the buckle, and the tongue may be released from the buckle by causing the release cover to be pivoted so as to raise the opening tab and cause the lock member to move to its open position, lifting the locking tab out of the tongue aperture 2. The structure of claim 1 wherein said lock member is pivotably supported with respect to the channel member on an axis extending between the side walls of the channel member at the end thereof which receives the tongue memher and the release cover is pivotably supported about an axis parallel to the axis of the lock member disposed at the other end of the channel member.

3. The structure of claim 1 wherein said locking tab has a first section which extends generally perpendicular to the base of the channel member when the locking member is in its closed position and a second section which extends perpendicular to said first section in a direction opposite to the axis of pivot of said locking member.

4. In a safety belt system fora vehicle including a pair of belt members each having one end fixed with respect to the vehicle, the first of said belt members having its other end fixed to a tongue member having extending sections and an aperture therein, a buckle operative to receive the free end of the second belt in an adjustable manner and to lockingly receive said tongue member so as to close the system, said buckle including:

a channel member having a relatively wide base and a pair of short opposed upturned sides;

a bar extending transversely across the width of the channel members adjacent to one end of the base and having its ends fixed in the short upturned sides thereof;

a lock member pivotably supported on the bar for motion with respect to the channel member and having a generally planar section which normally extends parallel to the base, a pair of upturned sides which are adapted to surround the bar and to be disposed on the interior sides of the short upturned sides of the base, an upturned lip disposed adjacent to one end of the base, a downturned tab formed from the planar section, extending downwardly from the center of the central section in the direction of the base and projecting in a direction opposite to the upturned lip and an upturned locking tab projecting from the end of the planar section opposite to the end having an upturned lip; and

an opening member extending generally parallel to the channel base and being pivotably supported with respect to the upturned sides of the channel and having an actuation area and an extending section, substantially separated from said actuation area, contacting the upturned tab of the locking member and being operative, when manually actuated, to urge in an upward direction so as to pivot the locking member with respect to the base.

5. In a safety belt system for a vehicle including a pair of belt members each having one end fixed with respect to the vehicle, the first of said belt members having its 7 other end fixed to a tongue member having an extending section and an aperture therein, a buckle operative to receive the free end of the second belt in an adjustable manner and to lockingly receive said tongue member so as to close the system, said buckle including:

a channel member having a relatively wide base and a pair of short opposed upturned sides;

a lock member pivotably supported with respect to the channel member, said lock member being formed of sheet material and having a generally planar center section with a pair of upturned opposed side members which are adapted to be pivotably supported between the upturned sides of the base so that the center section extends generally parallel to the base, having a lip upturned with respect to the center section extending generally transversely to the upturned sides of the base and being disposed at one end of the base so as to form a space between the lip and the base for receiving the tongue member, having an upturned opening section extending generally away from the base, from the end of the lock member opposite to that which carries the lip, and having a tab section intermediate its ends cut out and bent downwardly in the general direction of the base so that its free end projects in a direction opposed to the upturned lip; and

a manually actuable opening lever, having an actuation area and extending generally parallel to the base and being pivotably supported with respect to the upturned sides of the base for motion about an axis transverse to said upturned sides of the base, and having an extending section, substantially separated from the actuation area, operative to engage said lock member at the opening section thereof to cause said lock member to pivot with respect to the channel member so as to move said downturned tab away from said base, whereby the tongue may be inserted between the lip of the lock member and the channel base so that the downturned tab of the locking member extends through the aperture of the tongue and locks the tongue with respect to the buckle, and the 7 V 8 tongue may 'be released by manually actuating the 3,147,530 9/1964 Goldman. opening lever, pivoting the lock member with respect 3,170,211 2/ 1965 Van Noord. to the base so as to move the tab out of the tongue 3,197,832 8/1965 McCauley 24230.1 X aperture. 3,217,370 11/1965 Sharpsteen 24--230.1 X

R 5 3,226,791 1/ 1966 Carter.

Iifell'encgs Crtid by tlifAExanuner FOREIGN PATENTS N TE ST TES TENTS 1,334,209 6/1963 France. 2,888,724 6/1959 Anderson 24---230.1 X 2,999,288 9/ 1961 Warner. BERNARD A. GELAK, Primary Examiner.

3,013,317 12/1961 Weber 24230.1X 10 

1. IN A SAFETY BELT SYSTEM FOR A VEHICLE INCLUDING A PAIR OF BELT MEMBERS EACH HAVING ONE END FIXED WITH RESPECT TO THE VEHICLE, THE FIRST OF SAID BELT MEMBERS HAVING ITS OTHER END FIXED TO A TONGUE MEMBER HAVING AN EXTENDING SECTION AND AN APERTURE THEREIN, A BUCKLE OPERATIVE TO RECEIVE THE FREE END OF THE SECOND BELT IN AN ADJUSTABLE MANNER AND TO LOCKINGLY RECEIVE SAID TONGUE MEMBER SO AS TO CLOSE THE SYSTEM, SAID BUCKLE INCLUDING: A CHANNEL MEMBER HAVING A RELATIVELY WIDE BASE AND SHORT UPTURNED SIDES; A LOCK MEMBER HAVING A BASE AND A PAIR OF UPTURNED SIDES PIVOTABLY SUPPORTED WITH RESPECT TO THE CHANNEL MEMBER ON MEANS SUPPORTED BY THE UPTURNED SIDES OF THE LOCK MEMBER; SPRING MEANS CONNECTED BETWEEN SAID CHANNEL MEMBER AND SAID LOCK MEMBER AND OPERATIVE TO URGE SAID LOCK MEMBER INTO A FIRST, LOCKED POSITION WITH RESPECT TO SAID CHANNEL MEMBER; A LOCKING TAB EXTENDING DOWNWARDLY FROM SAID LOCKING MEMBER AND OPERATIVE TO ABUT THE BASE OF SAID CHANNEL MEMBER WHEN SAID LOCKING MEMBER IS IN ITS LOCKED POSITION; A CENTRAL UPTURNED OPENING TAB JOINED TO SAID LOCK MEMBER INTERMEDIATE THE UPTURNED WALLS THEREOF AND HAVING A TERMINAL END BENT SUBSTANTIALLY PARALLEL TO SAID LOCK MEMBER BASE; AND A RELEASE COVER PIVOTABLY SUPPORTED WITH RESPECT TO SAID CHANNEL MEMBER FOR MOTION ABOUT AN AXIS PARALLEL TO THE AXIS OF PIVOTATION OF SAID LOCK MEMBER, SAID RELEASE COVER HAVING A GRIP PORTION, A PAIR OF DOWNTURNED SIDE WALLS, A PLANAR TOP AND A POCKET MEMBER DISPOSED ON THE SIDE OF THE COVER TOP OPPOSITE THE BASE BETWEEN THE AXIS OF PIVOTAL SUPPORT OF THE COVER AND THE GRIP PORTION THEREOF AND BEING OPERATIVE TO ENGAGE SAID TERMINAL END OF SAID LOCK MEMBER, SAID RELEASE COVER HAVING A FIRST, CLOSED POSITION WHEREIN SAID SPRING MEANS, ACTING THROGH THE OPENING TAB OF THE LOCK MEMBER CAUSES THE RELEASE COVER TO BE CLOSED WITH RESPECT TO SAID CHANNEL MEMBER, AND A SECOND OPEN POSITION WHEREIN MANUAL FORCES ARE EXERTED ON THE RELEASE COVER SO AS TO CAUSE IT TO PIVOT WITH RESPECT TO THE CHANNEL MEMBER AND THE POCKET MEMBER ENGAGES THE OPENING TAB OF THE LOCK MEMBERS SO AS TO PIVOT THE LOCK MEMBER FROM SAID CLOSED POSITION INTO A SECOND OPEN POSITION, WHEREBY, WHEN THE RELEASE COVER IS IN A CLOSED POSITION THE TONGUE MAY BE INSERTED BETWEEN THE LOCK MEMBER AND CHANNEL BASE SO THAT THE LOCKING MEMBER EXTENDS THROUGH THE APERTURE OF THE TONGUE AND LOCKS THE TONGUE WITH RESPECT TO THE BUCKLE, AND THE TONGUE MAY BE RELEASED FROM THE BUCKLE BY CAUSING THE RELEASE COVER TO BE PIVOTED SO AS TO RAISE THE OPENING TAB AND CAUSE THE LOCK MEMBER TO MOVE ITS OPEN POSITION, LIFTING THE LOCKING TAB OUT OF THE TONGUE APERTURE. 